The invention relates to an anti-locking apparatus. An apparatus of this kind is known, see for example, German Offenl. 25 31 016 which corresponds to U.S. application Ser. No. 702,922 filed July 6, 1976; and to British patent No. 1,560,886.
In this known apparatus, the main brake cylinder piston is used for the purpose of pressure modulation. Integrated brake force amplifiers are also known which function with a travel-limiting spring, a brake valve and the associated hydraulic energy supply. When the energy supply is intact, the brake pedal push rod can perform an idle stroke corresponding to the stroke of the travel path simulator, until it comes into contact with the main brake cylinder piston.
This is necessary so that pressure modulation for the anti-locking function is possible over the entire pressure range.
The system disclosed hereafter may also be used in an external force brake in which the brake pressure only reaches the brakes through a valve. The German Patent No. 839,451 discloses a typical external force brake.